| The Multi-episode inversion of Songliao Basin has its special characteristics during the evolvement period of China east Mesozoic-Cenozoic basin. It is broad in scale and its related tectonic-stratigraphy development is remained comprehensively. Based on the traditional sediment-tectonic analysis, by the advanced methodology of low-temperature thermochronology, we do the quantitative or semi-quantitative research on the beginning time, developing episode of post-rift inversion structure and its tectonic-thermal history in Songliao Basin. This research contributes to build a comparative framework between the evolution of sedimentary basin and the kinematic reorganization of plate tectonic of adjacent plates, which can deepen our recognition on basin inversion system and procedure, and complete the kinematic model for east extension basins of china. Yaojia Formation and above middle-shallow layer are the most important and realizable exploration layer system. On the background of compressional structure, the movement of basin stratigraphic framework, sedimentary system, hydrocarbon trap, reservoir-forming combination and hydrocarbon fluid can be changed significantly and displayed conspicuously different styles compared with which in thermal subsidence and syn-rift period. As a result, this research also has the practical significance in oil-gas prospecting.This thesis is accomplished on the foundation of systematic summary and analysis for geological characteristics in Songliao Basin post-rifting, focusing on the apatite fission track (AFT) and zircon fission track (ZFT) low-temperature thermochronology aging test technology application of inversion structures in Songliao Basin postrift. The main results and findings are:1,This paper systematic describes and summarizes the main synthesized geological remarks of the post-rift inversion structure in the Songliao basin, included seismic, well logging,sedimentary, paleontology and structure.Based on the detailed sequence interpretation of the seismic profiles, we described and analyzed the geological features and structure properties of the main unconformities T11, T06, T03 and T02 which formed during the post-rifting stage of the Songliao basin. Beneath these unconformities, the truncation is very obvious. The boundary T11 truncates the axial region of the underlay regional gentle anticline and the red soil bed wide-spreads above T11. This shows that the Songliao basin was underwent a long expose and erosion stage in this sedimentary period. The boundary T07 and T06 above the T11 both appeared as a top truncation boundary of the westward prograding complex, which is very different from the both eastward and westward onlap in the underlay strata. We summarized the abundant inversion structures in this study area, determined 4 striking NE and NNE regional inversion fold-thrust belts from east to west in whole basin, and recognized the positive formal negative flower structure which formed related to the regional compression and is very significant for the hydrocarbon practice. The paleogeomorphology of main important boundary surface of was rebuilt with subsidence backstrip method, which is the conversion surface of the rift stage and post-rift stage (T3), the max flooding surface (T2), the inversion structure conversion surface (T11) and the inversion boundary surface (T06). The boundary T11 divides the developing model into two kinds:one is the transtensional ring-type and the other is the compressional ring-type. The isopach maps and the subsidence analysis indicates that the subsidence center of the Songliao basin migrated westward 4 times obviously at least and the migration span increased gradually from early stage to late stage. The analysis of the regional sedimentary system and the source setting relationship and the attribute extraction feature of the 3D seismic data shows that the source systems before the deposition of the Yajia Formation was extreme different from that after the Yajia Formation. This difference caused by the tectonic uplift of the east part of the basin and the new eastern source system began to form.2,The starting time of inversion structure in post-rift is re-determined. We also identify multi-episode inversion structure and qualitative describe its intensity of inversion and regional change.Comprehensive geologic tracer analysis shows that T11 boundary is an important structural disturbance boundary in the post-rift sequece filling. The phenomenon that has been identified in the east of boundary, such as uplift and denudation, palaeosol layer development, regional lake level decline, foreset bed formation from east to west on the boundary and eastern provenance emergence etc., show the boundary is the starting boundary in post-rift thermal subsidence inversion structure. The boundary developed in 88Ma, so evidently that about 15Ma earlier than formerly early Sifangtai (ie 73Ma). Moreover, inversion structures stage is composed of multiple unconfonnity and different periods subsidence center migration, this means such tectonic inversion structures is not single or instantaneous extrusion process but duration longer, multi period times, episodic evolution, and each inversion structure plays have experienced enhanced compressive stress-compressive stress weakening process. This study suggests that, in the late Cretaceous period, the basin has experienced at least four relatively strong tectonic inversion screen. The first phase inversion structure (the late Qingshankou, T11 boundary), took place at about 88.5Ma, the wide array of NNE swell slightly slow the fold zone developed from east to west; the second phase inversion structure (Nenjiang sections in the second stage, T06 boundary), took place at about 77Ma or so, east layer extrusion uplift, formation west forest overlap, black mudstone and eroded in some areas; the third inversion structure (the end of Nenjiang formation, also known as Nenjiang movement, T03 boundary), took place at about 73Ma or so, east layer uplift, five stage of Nenjiang formaition missing, truncated range westward; the fourth phase inversion structure (the late Cretaceous, T02 boundary), took place at about 65Ma or so and may continued to Cenozoic, a large number of early normal fault tectonic inversion, strong uplift and erosion in eastern, serious stratigraphic break.3,In view of the multi-episode tectonic inversion of post-rift in Songliao basin, lots of research on low-temperature thermochronology were made systemic and synthetically, this paper pick-up a series of AFT and ZFT parameter which reflect a lot of low-temperature thermochronology information about the occurrence of multi-episode tectonic inversion, and also analyze low-temperature thermochronology token systemic of different tectonic units in the basin.This paper analyzes area, the data of 30 AFTs,2 ZFTs and the AFT of the Jixi basin JiD6 well in the major tectonic unit of Songliao basin, and picks-up a lot of information about low-temperature thermochronology. In the length aspect of AFT, the multi peak values frequency distribution of the track length in eastern tectonic inversion zone indicate the occurrence of multi-episode burial-inversion-burial. The track length is short at large in the central sag zone, this phenomena indicates this area is the center of subsidence and the sample has been buried deeply so that the track annealing disappeared. The track length in western ramp is relative long, this indicates the process of tectonic-thermal evolution is relative simple and the thermal response of the late tectonic inversion is weak. In the statistical characters aspect of fission track age, including all of sample, the statistical peak value of AFT and ZFT single grain central age correspond with the unconformities and block kinematic recombination very well. According to the connection of age and burial depth, there were at least 5 episodes of uplift and temperature drop in the east,4 in the central area,and 2-3 in west. In addition, this paper confirms the depth of annealing threshold which is 389.2m in Quantou formation of eastern uplift area, the depth in Qingshankou formation of western ramp is 427m.Through the analysis on fission track age profile of 5 fission track well tie profiles, this paper considers that the age in inversion and terrace is big, but small in the sag and synclinal area, the bigger fission track age in southeast and northeast uplift area shows the tectonic inversion is early, the smaller age in west shows that the tectonic inversion is late. The character of the AFTA isopleths is that the southeast part is crowd, the age is also big, this indicates the intensity of inversion in southeast is big, and the time of inversion in southeast is early. The trend of AFTA isopleths is the same as the trend of principal stress in Cretaceous and Cenozoic of the basin. This paper gets the AFT data of Pu434 well and Gao111 well in Daqing for the first time, so far it is a reliable record of the earliest uplift(may not be the primary uplift) in the central sag of Songliao basin we can obtain. Integrating the interpretation of AFTA, this paper considers that the temperature of Quantou formation, Qingshankou formation, Yaojia formation and Nenjiang formation in Daqing Changyuan area increased rapidly, this area is also the central of subsidence, the T06 tectonic inversion in late Cretaceous made the formation which the samples locate in out off the zircon closure temperature (250℃). The Changyuan area was in the stage of inversion uplift from late Nenjiang formation to late paleogene, relative stable from 28Ma to present. It indicates that the inversion of Daqing Changyuan initiated in late Cretaceous, maintain the shape in late paleogene.4, Base on the substantive data of fission track, with the AFTsolve modeling sofrware, this paper obtains the curve of tectonic inversion thermal history in Songliao basin.This paper chose 4 typical samples of southeast tectonic inversion zone, central tectonic inversion zone and west tectonic inversion zone, and made the modeling thermal history analysis with Ketcham model and AFTsolve software. This thermal history curve shows that the thermal history varies a lot in different tectonic inversion zones, The time when the temperature of basin began to decline, is the earliest in the east, then in the center, the latest in the west, and the same trend in the rate of thermal history decline, it shows the character of inversion is strong and early in the east, weak and late in the west. The occurrence of temperature increase and decline, reflected by thermal history, is not linear, uniform and pure process, but the temperature increase or decline as a whole in some stage, at the same time, has a kind of sub-level rapid-slow-rapid-slow episodic rates variety, In general, in the stage of post-rift tectonic inversion, there were 2 stages of rapid burial temperature increase and 2 occurrences of temperature decline. There are two stages of rapid burial temperature increase, the first one is 106Ma to 88.5Ma,the other is 87Ma to 77Ma.Corresponding to the thermal subsidence of Quantou formation and the rapid subsidence lead by maximum flooding surface of Qingshankou formation and Nenjiang formation, The rate of temperature increase represent the character of big in the center and small in sides. The first occurrence of temperature decline is from 88.5Ma to 87Ma, the decline occurred in the whole basin, the second time is from about 78Ma to 77Ma, it only influence Daqing Changyuan area, the third time is about 73 Ma, the area influenced by it is big, it include most parts of basin, the fourth time is about 65Ma, the area influenced by it is the biggest, the whole basin uplift and temperature of it decline, the fifth time is from about late Cretaceous to late Paleogene. Every occurrence of temperature decline represent the its rate character of big in east and small in west, the trend of increase gradually. The occurrence of episodic temperature decline above corresponds very well to the formation of unconformity and its space variety,major inversion episode and its extent. This paper also obtains the thermal history curve of Jixi basin, the character of it is episodic, and its evolution trend and episode is the same as Songliao basin, this phenomena indicates the occurrence of temperature decline lead by tectonic inversion is regional, not only in Songliao basin. In addition, the time of temperature decline in Jixi basin is earlier, and the range of it is bigger than in Songliao basin, it shows the source of stress is nearer to Jixi basin, and compression stress is bigger.5,The plate kinematics reconstructions and evolution processes of West Pacific in Meso-Cenozoic are summarized emphatically. The kinetics model of the episode inversion structure during post-rifting period in Songliao Basin is rebuilt.Muti-episode tectonic deformations developed within Songliao Basin, which indicated that the regional stress field shifted many times and the long-distance intra-plate stress conduction raised by the stress of plate boundaries was correlative. Many times plate kinematics reconstructions happened in East of Eurasia plate since Mesozoic. The shift of direction and velocity of plate subduction may be the factor which drove the inversion structure during post-rifting period in Songliao Basin. Since Late Cretaceous (100Ma) the velocity of plate spreading increased sharply. During this pulsating period, the subduction of ocean plate toward to continental plate was the pulsating subduction.The important plate kinematics reconstructions beside the Pacific happened at the age of 88Ma, which induced the main compressive stress shift from NNW to NWW during a short interval. The boundary of Yaojia Formation(T11) developed at this time and the regional tectonic configurations were well correlative. Evidently, the boundary of T11 is the response to this plate kinematics reconstruction in basin. And then, the pulsating subduction of Pacific accelerated during 90-45Ma, when was consistent with the peak of episode inversion from Yaojia to middle Paleogene in Songliao Basin. Thus, this inferred plate pulsating subduction is just the kinetics background of the intense inversion structures in Songliao Basin and even the whole North-western China. The compressive stress induced by the process of subduction resulted in the discrepancy uplift of intra-plate from east to west. Series of boundaries of inversion structure formed.The temperature-time curve of Songliao Basin was well coupling with the kinematics reconstruction events of periphery plates. Before the age of 90Ma, the motion of plates kept steady relatively and the temperature of basin burial rose. By the appearance of Kula plate and the underthrusts of Izanagi plate during 88-65Ma, the activity of plates was pulsatile enhanced and the episode inversion structures developed. It was episode characteristics of buried temperature increasing-inversional temperature decreasing-another buried temperature increasing-another inversional temperature decreasing. The absolute velocity of Eurasia plate increased entirely at the age of 65Ma. And the compression stress induced by the subduction of the ocean plate with Eurasia plate resulted in large-scale inversion-uplift-temperature decreasing until the asthenia period of plate motion in middle-Eocene. Then the temperature was decreasing all along in western basin and increasing small-scale in eastern basin. The basin experienced uplift-temperature decreasing again when the Japan Sea shut up at the age of 17Ma. Since then the basin began to bury and temperature increasing small-scale until present. The evolution of tectonic and thermal history of Jixi Basin in the east put up the similarities with Songliao Basin.
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